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crops that could be produced in the 
absence of polluted waters. 
Conservationists believe that no in- 
dividual or group of individuals has 
the right to destroy publicly owned 
resources needlessly or for their own 
immediate profit. Both from an eco- 
nomic and a public health standpoint, 
it is becoming increasingly important 
to clean up the polluted waters and 
thereby to protect human health and 
restore the biological productivity of 
part ofour natural-resource machinery. 
There is one way to accomplish this 
program. It is necessary, first of all, 
to stop immediately any new pollution 
of water; it is then essential to put into 
effective operation a program for abat- 
ing the existing sources of pollution. 
The Role of Vegetation 
Reforestation or revegetation is the 
first line of defense in both erosion 
control and water management. Too 
late has the public realized the mistake 
in cutting forests recklessly, and the 
wastefulness of allowing land to pass 
into an irresponsible ownership in 
which no thought was given to the 
future. Still, much progress has been 
made in the last 40 years in public 
understanding of the necessity of re- 
vegetation, and much public money 
has been spent in buying back lands 
suitable for reforestation. 
Much of the rough and poor land 
of the western States is in public 
ownership and capable of being man- 
aged in large blocks with maximum 
permanent return. The _ publicly 
owned lands in the West are valuable 
chiefly for timber production, water- 
shed protection, and recreational pur- 
poses. Some of them have value for 
grazing, but many of the more arid 
regions quickly deteriorate when over- 
grazed, a mistake that is easy to make 
in an arid land particularly during a 
drought period. This nation should 
not make the mistake of allowing 
highly productive lands to pass into 
private hands for the purpose of ex- 
ploitation or destruction, for ulti- 
mately they must then be brought 
ANNUAL REPORT SMITHSONIAN INSTITUTION, 1948 
back into public ownership for re- 
vegetation at great public expense. 
We should learn by the mistakes of 
the past. The rough and mountain- 
ous lands of the country, the arid 
grazing lands, and the deserts that 
are not suitable for agriculture should 
always remain in public ownership 
where they can be managed for the 
protection of all interests and still be 
made to produce some return. 
The basic concept of conservation 
may be said to be the permanent re- 
vegation of all lands not suitable for 
agricultural development. Such lands 
in which rainfall is adequate should 
be restored to forests and when re- 
stored, they should be placed under a 
program of management such as will 
produce a sustained yield. In that 
form they will return their greatest 
value to the nation as well as to the 
community in which they are located. 
The more arid lands should be re- 
turned to grass or other suitable forms 
of vegetation. 
One of the great mistakes of World 
War II was the plowing up of vast 
areas in the Great Plains country 
which, conservationists hoped, had 
been permanently placed in grass 
following the spectacular dust storms 
of the 1930’s. Much public money 
was spent on the effort to vegetate 
these lands. Now with high prices and 
a little better rainfall, it has been prof- 
itable to gamble on cropping this 
land. It is a gamble and droughts 
will again return to the plains. Will 
these landowners have either the re- 
sources or the understanding to put the 
land back into grass once prices go so 
low as to render the gamble unprofit- 
able or when drought begins to cut 
returns to the same point? Especially 
when our Government supports a 
program of high farm prices it is a 
good guess that they will not and that 
the public will again be called upon 
to pay the cost of returning these lands 
to the only use for which they are 
basically fitted. The protective vege- 
tation can be utilized for grazing by 
livestock or wild animals. It can be 
